Bar joist



March '13, 1928.

T. A. LUCY BAR JOIST Filed Aug.

30, 1926 2 Sheets-Sheet 1 11 F. fl .13 9

,6 7 2 fj- :/Z7

1 W f E 12 9 3 w Q 7/90/14 5 A. ZVCY) March 13, 1928. 1,662,752

. T. A. LUCY BAR JOIST Filed Aug. 30, 1926 2 Sheets-Sheet 2 1o 1 63mm I \AL l 4 fi o/was A. 400/,

22 5 *3 WW %W.

Patented Marl 13, 1928.

UNITED STATES PATENT OFFICE.

THOMAS A. LUCY, 0F ASHEVILLE, NORTH CAROLINA, ASSIGNOR TO INGALLS STEEL PRODUCTS COMPANY, OF BIRMINGHAM, ALABAMA.

BAR 30181.

Application filed August 80, 1926. Serial No. 132,400.

This invention relates to fabricated metallic joists or trusses, and more particularlyto the type of joists known as bar joists, whlch consist of upper and lower bars or chords connected by a webbing, and used for roof and floor construction 1n buildings.

The bottom chords of such joist are usually bent upward at the end and secured to a gusset plate to form a supporting member. Considerable difficulty has been encountered by the breaking and coming apart of the end section due to the present form of the gusset plate and the method of attaching it to the chords.

One of the objects of this invention is, therefore, to provide a joist having the required rigidity and strength, especially at its ends, with minimum material. In the use of such a joist considerable difliculty has been encountered in properly anchoring the same at its end to its support, and also in forming an effective ceiling support at the place where the bottom chords have been bent upward out of their normal plane.

Other objects, therefore, of this invention are to provide means for effectively attach-.

ing and anchoring the bar joist to its support and to provide a simple and effective means for supporting the ceiling therefrom near its ends.

Further objects will appear from the detail description taken in connection with the accompanying drawing in which:

igure 1, is aperspective view showing the end of a bar joist embodying this invention;

Figure 2, is a view similar to Figure 1, but showing an additional feature;

Figures 3 and 4 are similar views showing other embodiments;

Figure 5 is a side view of the embodiment shown in Figure 4;

Figures 6, 7, and 8 show details of construction; and

Figure 9 is a view similar to Figure 4, showinganother embodiment of the invention.

Referring to the accompanying drawing, 1 designates the top chords of such a bar joist, and 2 designates the bottom chords, connected together by a web 3. All of these elements are preferably constructed of rolled steel bars of any commercial cross section. The top chords 1 and bottom chords 2 receive therebetween the web 3, these being welded together at each point of intersection.

The bottom chords 2 are bent upward at a point'4 to a point 5 and bent at oint 5 to a plane parallel with chords 1. t the end of the joist and between the chords is a gusset plate 6 constructed preferably of plate steel. This gusset plate extends from the end of the joist to a point beyond point 5 but short of point 4, and in this invention the chords are continuously Welded thereto at its upper and lower edges throughout its entire length. A bearing plate 7, preferably of plate metal, is placed beneath the chords 2 and gusset plate 6 from the point 5 to the end of the joist and secured thereto preferably by tack welding.

The joist rests upon the bearing plate 7, and may be placed upon any suitable sup port, such as I-beam girder 8. A U-shaped notch 9 is formed in the gusset plate 6, and an anchor 10 formed preferably of rolled steel rod with a hook 11 formed at one end is adapted to engage the notch 9, while at its other end has formed a suitable anchoring element 12 adapted to engage the joist support. If the support is an I-beam, as in Figs. 1 and 2, the end of the anchor 10 may be formed into a hook 12to engage the beam. If the end of the joist abuts masonry, as in Figure 3, the end of the anchor 10 may be formed into a T-anchor 13.

Referring to Fig. 2, a rod 14 is attached, as by hooking, tying, or welding, at one end to the chords 2 at the point 4 and extended in the normal plane of the chords 2 toward the end of the joist. The. other end of rod 14 is turned up vertical. The rod 14 is also supported by a rod 15 fastened in a hole 16 in the gusset plate 6 in any suitable manner, as by forming a hook on the end to engage the hole, and is fastened to the rod 14 as b hooking, tying or welding. Furring rods 1 are placed transversely upon and across the rod 14 and the chords 2'. Beneath the rod 14 and the chords 2, and attached thereto and to the furring rods 17, is placed metal lath ing 18, upon which the plaster ceiling may be formed.

Figures 4 to 9, inclusive, show the method emplo ed in forming the end of the joist and provi ing, an anchor where the joist is comined with a. concrete beam 19. The gusset plate 6 and bearing plate 7, Figures 4, 5, and 9, do not extend to the end of the joist but leave the chords 1 and 2 open to a point where a T-anchor 20 is attached at the end. To set the end, as shown in Figures 1 to 8, inclusive, having extended gusset and bearing plates, into the concrete would makea less perfect bond and would materially weaken the efliciency of the concrete beam.

Figure 6 shows a standard T 20, formed preferably of plate steel, which is welded to chords 1 and 2, as snown in Figures 4 and 5. The end of the joist should extend well inside the stem of the beam. In practice the joists are furnished in standard sizes and where the end extension is not long enough to reach inside the beam, a T-anchor 21, constructed preferably of plate steel, having a longer stem 22, is welded at the end of the joist to the chords, as shown in Figure 9. Instead of using a T-anchor, in the form shown in Figures6 and 7, the anchor may be formed, as shown in Figure 8, of a stem or shank 23 having a pin 24 inserted perpendicularly therethrough and welded.

Figure 4 shows the joist resting upon the concrete form 25 for the beam 19, and Figure 5 shows a beam in conjunction with the joist and the supported concrete floor 26.

It will thus be seen that the invention accomplishes its objects. The joist, while of rigid construction, is of light weight and the material is a minimum. By extending the gusset plate for some distance along both upper and bottom chords and by welding the same continuously thereto, a strong and rigid construction is provided. The attaching means is not only simple in construction but also enables the joist to be rigidly attached to its support. The means provided for supporting the furring rods at the end of joist, where it is desirable to bend the lower chords upward out of their normal plane, is simple and etficient.

It is obvious that various changes may be made in the details of construction without departing from the spirit of this invention; t is to be understood,therefore, that this invention is not limited to the specific details shown and described.

It will be noted that, in accordance with this invention, there is provided a bar joist having upper and lower chords with a connectmg element or gusset plate joining these chords at each end of the joist; and anchor is attached to each of these elements or gusset plates, and this anchor is adapted to hook over its supports or beams so as to tie the same together. By attaching the anchor to the connecting element or gusset plate, a firm anchorage is not only provided, but the sugports or beams are firmly tied together in or er to brace the entire building structure a ainst transverse or torsional stresses. '1 e connecting element or gusset plate comprises a rolled section, having a web joining the chords and having a flange adapted to gusset plate secured to said chords, said gusset plate having means thereon to engage an anchor. 7 p i 2. A bar joist having upper and lower chords consisting of pairs of bars joined by a web and having a gusset plate at its end with a notch in the inward end of said plate adapted to engage an anchor.

3. A bar joist having upper and lower chords consisting of pairs of bars joined by a web and having a gusset late at its end and an anchor engaging said gusset plate adapted to secure said joist.

4:. A bar joist having upper and lower chords consisting of pairs of bars joined b a web and having a gusset plate at its en and an anchor element having one end engaging said gusset plate and the other end adapted to engage the support of said jolst.

5. A- bar joist having upper and lower chords, said lower chords bent upward out of their normal plane to engage a gusset plate, and a rod extending below said gusset plate in the normal plane of said lower chords and supported from said gusset plate.

6. A bar joist having upper and lower chords, said lower chords bent upward out of their plane to engage a gusset plate, a rod extending below said gusset plate in the normal plane of said lower chords, having one end secured to said lower chords and its other end turned upward vertical to said plane, and a support for said rod engaging said gusset plate.

7. A bar joist having upper and lower chords, said lower chords bent upward out of their normal plane to engage a gusset plate, and said gusset plate being adapted to engage both a ceiling support and an anchor for said joist.

8. A bar joist having upper and lower chords consisting of pairs of bars and joined by a web and having its end portion formed by a gusset plate secured to said chords, and a transverse anchor at the end of such joist.

9. A bar joist having upper and lower chords consisting of pairs of bars and joined by a web, a gusset plate and an anchor at the end of such joist, said gusset plate and said anchor being spaced to provide an open space between said chords.

10. A bar joist having upper and lowen *toeach of said plates and adapted to hook over its support.

13. In a buildin' structure having sup ports, a bar joist aving upper and lower chords, a gussets plate joining said chords at,

each end of the joist, and a transverse anchor on the end of each gusset plate.

14. In a building structure having supports a bar joist having upper and lower chor a gusset plate joining said chords at each end of the joist, and an anchor bar attached to each gusset plate and adapted to hook over its support.

15. In a building structure having supports, a bar joist having upper and lower chords, and an element at each end of the joist and comprisin a rolled section having a web joining sai chords and having a flange adapted to bear on its support, each element having an anchor adapted to tie adjacent supports together.

16. In a building structure having supports, a bar joist having upper and lower chords, and an element at each end of the joist and 'comprisin a rolled section having a bearing flange an having a web extendin inwardly beyond said flange and joining sai chords, each element having an anchor adaptedto tie ad'acent sup orts together.

In testimony w ereof I a my signature this 5th day of August, 1926.

THOMAS A. LUCY. 

